There are some refineries equiped with a desalter which removes impurities contained in crude oil and reduces fouling and corrosion in refinery equipment.
This article is based on the literatures, home and abroad, and summaries what impurities are contained in crude oil, what benefits can be gained by eliminating these, Particularly putting emphasis on the relation between the corrosion and desalting, what theories of desalting are, and what financial sawings are expected from desalting.
Desalting is said to be good for reduction of fouling problem on equipments, but this is not always the case with prevention of corrosion. There is no agreed opinion about its effectiveness, for it depends on what type of crude oil is processed and what type of plants are installed in the refinery. Therefore, budget justification for desalting is the problem for each refinery to decide under consideration of its refinery situations.
If, in the near future, desulfurization plant of residuum is forced to be installed from view point of air pollution, the two-stage desalting might be closed up.
